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Navigation: Output functions

Alternator control

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Alternator voltage control


Voltage control

Enables or disables the output voltage control duty.


Target voltage

The target alternator voltage (V).


PWM frequency

PWM frequency (Hz) to use on the output. <-- Make sure to use the correct frequency of your alternator by checking with the manufacturer.


Min control duty

Minimum duty to be applied to the output.


max control duty

Maximum duty to be applied to the output.


P gain

P-value in the PI control regulation.


I gain

I-value in the PI control regulation.






The above is an example to control the Ford Coyote 5.0 alternator, working at 120Hz, but MAKE SURE TO ENTER YOUR ALTERNATORS CORRECT FREQUENCY. <-- To low frequency can cause sever damage on your engine and/or alternator.




PID control

PID is a "closed loop" control algorithm (instructions for solving a task) used to adjust a control value, (eg a idle valve position). In order to process actual values ​​(eg engine speed ) to match the desired TARGET value (eg, idle speed ) then adjusts the PID-algorithm control value according to these three elements.




P is used to bring the value close to the target.

I is used to bringing the error to zero.

D is used to dampen the response.



Setup process

P and I must always be used (not allowed to be zero), D is optional and not always necessary.


Usually starting by increasing the P and I together (using the same values) until it becomes slightly unstable.

Bring in some D to counteract that, and then fine-tune each value. Often by reducing P and increasing I.

The overall goal is to use as high values as possible while still having a stable response.

Then decrease all values a bit to add some safety margin to prevent overshoot or oscillation.



Typical problems (P)

Too low: Does not reach target, slow response.

Too high: Fast oscillation.


Typical problems (I)

Too low: Does not reach the target, slow response, overshoots and recovers slowly.

Too high: Oscillation.


Typical problems (D)

Too low: Overshoot.

To high:  Oscillation.






The above "%/100" means % per 100 error.

Example: 100 error --> 100% duty outputed.